(2005 F350) Intermittent sticking turbo (No Boost)

Fordtechnician · April 19, 2006

I had this truck in about 600 miles ago, 3 wks. When the no boost situation came about, you could shut the truck off and restart it and the turbo worked. After testing, I ended up replaceing the VGT. It worked fine. Owner came in yesterday, same thing.

I have read about turbo units for trucks that don't get driven a lot. Do I want one of these? What is the part number? Or am I barking up the wrong tree? The new Ford parts catalog only lists one turbo for this truck.

LARRY BRUDZYNSKI · April 19, 2006

Which turbo are you putting on? The current # is

5C3Z6K682CA. My thinking would be why the VGT is failing, what else is going on with the truck?

Looks like you probably need to dig deeper.

Keith Browning · April 19, 2006

If you guys are unaware of TSB 06-4-12 then go to FMCDealer and print it out! It is a comprehensive guide on Coking Deposit Diagnostics and Service Tips for the 6.0L Diesel. In most cases, it will help find the root cause of excessive coking leading to failures of the Turbocharger and EGR valves. I have been able to determine poor fuel quality and excessive idling as the root cause.

And don't be afraid to perform this one - it pays STRAIGHT TIME.

Another cause of sticking turbos is long periods of non-use. If a "clean" turbo sits with moisture in the system, surface rust can form in the housing causing the unison ring to stick. Sometimes a tap with a hammer and an active road test will cure those.

Fordtechnician · April 19, 2006

What does shutting it off and restarting it have to do with it?

HGM · April 19, 2006

If you cannot find the number, call hotline and ask them for the number for the "machined recess" turbo.. All 6.0L turbos are going to be of this design but curently you may get old stock.. Its not an issue if the guy drives the truck.. Its mainly for the truck that sits and/or idles alot.. Fuel quality is definatly a big point.. Advise the customer to use the Motorcraft fuel treatment..A couple of tankfulls of it should make them believers...

Fordtechnician · April 19, 2006

This guy is a firm believer in motorcraft additive.. He has it figured out that he spends $2.00 woth of product every tank full and saves $20.00. Impressive.

charley425 · April 19, 2006

Now let me see if I have this correctly.I can't let the truck sit, I cant let the truck idle, and I have to put some type of additive in the fuel system for it to perform correctly. Yea !

gasgasman · April 19, 2006

Now let me see if I have this correctly.I can't let the truck sit, I cant let the truck idle, and I have to put some type of additive in the fuel system for it to perform correctly. Yea !

Yes. That is true for ALL diesels equipped with an EGR valve.

The On The Road diesels(18 wheelers) are having the same problems.

HGM · April 20, 2006

Now let me see if I have this correctly.I can't let the truck sit, I cant let the truck idle, and I have to put some type of additive in the fuel system for it to perform correctly. Yea !

The issue is that we never realized this before, its always been an issue, now we have moving parts and systems that make the problems evident to the customer.... Diesel engines were not made to idle,they were made to work, and do so at optimum Tq/HP output.. They actually cool off when idling(too cold).. The fuel quality sucks, the regulations arent strict enough and the fuel is suceptible to becoming a perfect breeding ground for micro organisims.. And if anything metal sits long enough it rusts or corrodes..... Maybe there's a reason that some folks dont have problems with their trucks... Maybe they understand how they work.. I know several techs with 6.0's and love them, even with modifications, but they know how to work on them and how to treat them..

LARRY BRUDZYNSKI · April 20, 2006

I've found that most people that own these trucks go to the local fuel station and don't realize what quality fuel that their getting. When we have a quality issue with fuel, the best advice we can give is to inform the customer that when truckers refuel they know who has the best quality fuel and the truck stops are always busy. Thus it makes sense that the t/s always has fresh diesel.

Jeff Adema · May 6, 2006

I had a 04 F250 in not long ago, customer complaint was very similar to the original complaint in this thread. The dealers he had taken it to couldn't/wouldn't do anything, so he came here. What I found was a stuck unison ring in the turbo, there were actually grooves worn into the slots from excessive use that position, there was virtually no VGT action at all. It would cause overboost, which blew out his original intercooler. I found the terminals of the VGT connector and the EGR connector very loose while performing a pin drag test. It all smelled very familiar, as I'd run into this type of problem before at a Mack dealer when they put CEGR and VGT on they're trucks. Loose connections, poor VGT and EGR control, poor performance/overboost, etc. ad nauseum. Just thought I would share.